SPN 597
STOP
Brake switch
The truck's control module (ECU) reports a fault on: Brake switch.
SPN 597 means a truck control module (ECU) flagged a fault on brake switch, part of the Brakes / ABS system on heavy-duty diesel trucks. DERATE rates it STOP: park safely and do not keep driving until it is checked. Part usually replaced: Brake light / pedal switch, $25–$140 (aftermarket to dealer) plus 0.3–1 h labor.
Brakes / ABS
Can I keep driving?
No. Stop: park the truck in a safe place and do not keep driving until it is checked. DERATE treats this code as safety-critical.
Part usually replaced
Brake light / pedal switch
$25–$140 (aftermarket to dealer)
Labor: 0.3–1 h
USD, part only. Labor is billed at the shop's hourly rate.
Data: DERATE verified base, updated October 2026
Related codes
Read it off your own dash
Take one photo and DERATE tells you whether you can keep driving.
Ask DERATE
DERATE assists. It does not replace inspection by a qualified technician.